|
INVESTIGATIONS
|
Stone |
RI min |
RI max |
Biref min |
Biref max |
Dens min |
Dens max |
Colour |
Locality |
Info |
nx min |
nx max |
ny min |
ny max |
nz min |
nz max |
Spectrum |
UVS |
UVL |
Reference |
|
muscovite |
1.53 |
1.58 |
|
|
2.83 |
2.85 |
pink |
Brazil |
0.76 - 23.19 ct, RI weak shadow
reading |
|
|
|
|
|
|
no
features |
inert |
inert |
Gems & Gemology 2006 Spring,
p65-66 |
|
muscovite |
1.57 |
1.58 |
|
|
2.74 |
2.76 |
emerald
green |
Tanzania |
0.25-1.25 ct, polycrystalline
structure, weak shadow reading of
RI |
|
|
|
|
|
|
Cr-lines |
|
|
Gemmologie, Zeitschrift der Deutschen
Gemmologischen Gesellschaft 2010 59/3-4,
p109-115 |
|
muscovite |
1.57 |
1.57 |
|
|
2.8 |
2.8 |
green |
|
bead,
9.80mm |
|
|
|
|
|
|
Cr-lines |
|
|
Gems & Gemology 1992 spring,
p |
|
muscovite |
1.58 |
1.58 |
|
|
2.89 |
2.89 |
emerald
green |
|
3 cabochons up to 1.5ct, spot
RI, polycrystalline, emerald imitation,
=fuchsite |
|
|
|
|
|
|
|
|
|
Gems & Gemology 2002 Summer,
p183 |
|
muscovite |
1.6 |
1.6 |
|
|
2.8 |
2.9 |
light green to intense
green |
Ethiopia |
2.56 ct, aggregate (remains lit
under crossed polarizers), RI difficult to
read |
|
|
|
|
|
|
|
inert |
inert |
Gems & Gemology 2013 Fall,
p183 |
|
muscovite |
|
|
|
|
|
|
yellow |
Itinga, Minas Gerais,
Brazil |
|
|
|
|
|
|
|
|
|
|
Gems & Gemology 2012 Fall,
p225 |
TABLES
|
Stone |
RI min |
RI max |
Biref min |
Biref max |
Dens min |
Dens max |
nx min |
nx
max |
ny min |
ny max |
nz min |
nz max |
Reference |
|
Muscovite |
1.53 |
1.61 |
0.034 |
0.042 |
2.82 |
2.86 |
1.530 |
1.552 |
|
|
1.580 |
1.610 |
Tables of Gemstone
Identification, Roger Dedeyne, Ivo Quintens, 2007
|
|
Muscovite |
1.55 |
1.615 |
0.03 |
0.042 |
2.75 |
2.91 |
|
|
|
|
|
|
Gemmo.eu
|
CAUSE OF COLOUR
|
Stone |
Colour |
Cause of
colour |
Reference |
|
Muscovite |
green |
Cr³+ |
http://minerals.caltech.edu |
|
Muscovite |
reddish-purple |
Mn³+ in octahedral
sites |
http://minerals.caltech.edu |
|
Muscovite |
yellow |
Caused by the rising absorption
toward the blue and ultraviolet regions between 400 and 500 nm, which
shifts the reflected and transmitted light toward a mixture of red to
green that the eye interprets as
yellow |
Gems & Gemology Fall 2012,p
225 |
MINERAL INCLUSIONS
LOCALITIES
CHEMICAL DATA (%)
|
Stone |
Colour |
Locality |
Reference |
SiO2 |
Al2O3 |
MnO |
Na2O |
K2O |
Cs2O |
H2O |
F |
Rb2O | |
|
Muscovite |
pink |
|
Brazil |
Gems & Gemology 2006 Spring
p66 |
45.32 |
36.93 |
0.12 |
0.4 |
10.41 |
0.13 |
4.29 |
0.33 |
0.37 |